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I have a set of old batteries, 6 V flooded Golf Cart batts. They are probably 5-7 years old. Not cycled much though. Probably have 1-2k miles on them. Maybe even less. They were in an EV that was sitting. Anyway, I removed them and put them in my other car. I am charging them now. The other car is only 72 V, so I took the best 12 out of the 20 from the other car. I used a very slow charge rate, about 3 Amps. I used the BC-20, set for max voltage of 7.5 V / batt (90 V total) and a charge rate of 3 Amps. I don't plan to actually go that high though. I have been charging them for a while now, and the voltage is slowly going up, as expected. They are pretty well in balance. Supposedly, I should stop around 7.2 V / battery (86.4 V). But, the batteries are aged, and Lee's infortion on PBA batts in the library says I may never get there. So, when do I stop? How do I know I am getting a full charge without overcharging them? I don't want to
undercharge them either. I am watching for gassing and keeping the charge rate very low. But, I'm not sure what to expect. The batts haven't been cycled in at least 2.5 years. Just due to time constraints, I'll probably have to stop the charge in a few hours, and I expect the pack to be about 82.5 V at that time, no battery up to 7.2 V. Then, it will sit until I try again. I can slowly discharge them as well and cycle them a few times if that is the best way. Should I cycle them under heavy EV load or use something like a 100 W bulb, which will be very very slow?


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